We want to get here. Five days, now, and counting, until robin is right here at the desk. Another step on her journey, being walked, or really run and jumped by abc's john schriffen. He is playing in the nba all-star game in houston, where robin had hopes to do it. And to make sure he does our all-star and hall of famer proud, john's been getting tips from some of your favorite celebrities, all-time great players and favorite person. Reporter: It's a daunting challenge to stand in for one of the game's true greats. I am working hard to make my comeback soon, too. I am bummed that I can't be there at the game. But john is there. And, john, you're going to score some points for me, right? I'm counting on you. Reporter: Thanks, robin. I will try my best tonight. But I can't wait to see your comeback on wednesday. I've been drawing the help of nba legends. Among them, clyde drexler. Bruce bowen. Bruce playing against me. And both have volunteered to help me get ready. Most guys they do an nba workout in 15 minutes, they're dead-tired. Reporter: This could be it for me. Bruce and clyde, along with chandler parsons, know something about staying fit. They are ambassadors, encouraging children to be active. We have to focus on kids getting outdoors more. There's the ball. Reporter: Also about me not embarrassing robin in tonight's celebrity all-star game. The ball slipped. Reporter: I'll blame it on the ball. Thank you. Thank you. We're going to work on it. And tomorrow night, we're going to do it in the game. The ball didn't slip. He's worried about playing my team. Reporter: Maybe I can't dunk like chandler. But I do have a secret weapon. High school basketball coach lawrence roberts. Did I mention he's robin's older brother? I have to make robin proud. Listen, here's what you need to do. Shoot the ball. Shoot the ball. Shoot the ball. Did I say shoot the ball? Reporter: Give me one or two go-to moves. There you go. Nice. Reporter: I like this. All right. Reporter: This is going to work tonight? Absolutely. Reporter: Let the game begin. For "good morning america," john schriffen, abc news, houston. One, two, three. Team robin. That's awesome. Bruce bowen, my former colleague at espn, he's going to be jawing all game. You can see it. The celebrity game tonight at 7:00 eastern, on espn. Enjoy.

This transcript has been automatically generated and may not be 100% accurate.

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